This application represents an improvement over prior copending application Ser. No. 729,830, filed on Oct. 5, 1976.
This invention relates generally to dispensing devices and more particularly to an aerosol dispenser which does not rely upon chemical propellants and the like for discharging the product dispensed.
Although aerosol dispensers are exceptionally convenient spray devices and have enjoyed a growth pattern achieved by few packaging systems, they have many disadvantages. For example: manually operated spray pumps are unable to duplicate aerosol dispenser performance; recent evidence indicates that the ozone layer is being depleted by the propellants used in aerosol spray devices; many deaths and illnesses are reported each year due to the use or inhaling of chemical propellants by persons seeking to obtain drug related effects therefrom; shipping, handling and storing of the conventional, pressurized containers requires special procedures; pressurized aerosol dispensers require special disposal precautions; strict requirements must be met and procedures followed in connection with the filling of aerosol dispensers utilizing chemical propellants; and many products cannot be packaged in such devices because of chemical incompatibility between the product to be dispensed and the chemical propellant.
Many efforts have been made in the prior art in order to overcome one or more of the difficulties enumerated above. For example, attempts have been made at developing finger operated pump dispensing devices or trigger dispensing devices which do not rely upon chemical propellants for effecting pressurized discharge of the product. However, such devices have only partly solved the problem of providing a convenient yet safe and effective dispensing device. For example, users of the finger operated pump and trigger devices experience finger fatigue, and because of the action or force exerted to operate such devices it is difficult for the user to consistently achieve accuracy in spray direction. Further, such devices do not provide for duration spray and except for some devices the pressure does not remain constant throughout a discharge cycle. Thus, with such devices a fine spray might be achieved initially during a discharge cycle but near the end of the discharge cycle the pressure deteriorates rapidly and the spray deteriorates into a wet stream or dribble.
There are many other problems with existing propellant operated aerosol devices and with pump or trigger operated spray devices. For example, when chemical propellants are used the product discharged may feel cold to the skin of the user, and the design and structure of the containers is determined by the presures which must be withstood. On the other hand, some finger operated pumps and triggers are not capable of generating sufficient pressure to obtain a fine mist or suitable atomized spray for use with many products such as personal care products in the nature of cosmetics and hair sprays and the like, and the duration of spray obtained is limited in most instances by the length of stroke of the pump or trigger.
U.S. Pat. Nos. 3,761,022 and 3,921,861 are exemplary of some of the prior art efforts to solve the above problems. Other patents which disclose various approaches to solving the problems enumerated above are: U.S. Pat. Nos. 3,746,260, 3,777,945, 3,790,034, 3,799,448, 3,865,313 and German Pat. No. 2,315,467 of 1973.
All of the prior art patents enumerated above are either excessively expensive and difficult to manufacture and/or do not provide sufficient pressure for the desired spray pattern and/or do not provide sufficient spray duration and/or the user experiences finger fatigue and spray misdirection when using the devices.
The present invention provides a structure which solves the above problems relating to spray duration and pressure, and yet is economical to make and easy to use. Additionally, the device of the present invention may be made of biodegradable materials, or inexpensive, recyclable aluminum. In fact, the device and the containers associated therewith can both be readily made from inexpensive, recyclable aluminum.